The inventions described herein relate to wheelchair restraint systems and more particularly to improved spring-loaded track fittings for rapidly and safely securing a device to a floor track in a vehicle.
Conventionally, buses and vans equipped to carry wheelchairs and the like are provided with a pair of parallel slotted floor channel-shaped tracks into which one or more anchors can be inserted. Each track has a series of spaced-apart circular openings. Between the openings the open upper side of the channel-shaped track narrows. Anchors are designed with lugs extending laterally from the lower part of the anchor. The lugs fit through the openings in the track, and the anchor is moved such that the lugs lie underneath the narrowed potions of the upper side of the channel-shaped track to prevent removal of the anchor from the track. The anchors are and tracks are designed so that the anchor may secured at any selected position along the length of the track. Such anchors include a spring-loaded plunger, the lower end of which contains a post that passes through spaced-apart openings in the track to keep the lugs in alignment with the narrowed portions of the upper side of the track. Upon release of the spring, the sides of the plunger engage with the track at any selected position.
While such fittings are generally effective they are not without their disadvantages. Any asymmetry can result in a moment or leverage such that forces applied to the fitting during a sudden deceleration or crash situation, can cause bending or twisting of the fitting or of the track itself so that the fitting jams in the track and no longer slides freely within the track. There is a need, therefore, for an improved track fitting that spreads the applied load along a longer length of the fitting and track so as to prevent or at least minimize such bending or twisting of the fitting and/or the track. In addition, if the posts on the plunger do not properly engage the openings in the track, the anchor can accidentally disengage from the track. Since the anchor is typically very close to or at ground level, it is sometime difficult to see whether the anchor and plunger have properly engaged the openings in the track.
One of several objects of the system described herein is to provide a track plunger fitting that has easily seen indicia to confirm to the installer that an anchor is properly engaged in a track.
Yet another one of several objects of the system described herein is to provide an anchor that engages a plurality of adjacent holes in a conventional floor track so as to eliminate or reduce any twisting action on the fitting. In order to accommodate a dual plungers without increasing the overall height of the device, a split plunger with overlapping heads may be employed.
By one aspect of the system described herein there is provided a track fitting comprising an anchor with at least one track engaging lug extending from a lower part of the anchor; a plunger carried by the anchor, the plunger having at least one post; the plunger being moveable between an extended position and a retracted position; the plunger in the retracted position allowing insertion and translation of the lug of the anchor in a track; the plunger in the extended position being such that the at least one post is in registration with an opening in the track to restrict translation of the anchor and restrict removal of the anchor from the track; and visual indicia on an outer portion of the fitting defining a visual confirmation that the plunger is at least approximately in its extended position locking the anchor in the track.